


Stultus

by royalreddeath



Series: Radiant Mermaids [1]
Category: Kingdom Hearts
Genre: Multi, Talking, mermaid au
Language: English
Status: In-Progress
Published: 2019-02-19
Updated: 2019-02-23
Packaged: 2019-10-31 11:18:35
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 2,901
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17848448
Author URL: https://archiveofourown.org/users/royalreddeath/pseuds/royalreddeath
Summary: Lea + Isa swimming to go look at the moon on the beach, they get interrupted. Probable multi-chapter, will be a multi-work.





	1. Chapter 1

**Author's Note:**

> Title is mostly a placeholder.

“Hey, Isa, you remember that time I almost killed you?”

“You’re going to have to be more specific than that, Lea. You do that regularly.”

Lea rolled his eyes and swam up and above Isa, reaching down and dangling his arms in front of his best friend as they swam together. He silently recalled when he had to be more careful around Isa, glad for that time being over. “Nah, you know what I mean. I’ve never actually almost killed you.”

“Didn’t you just ask about the time you did?”

“Yeah, yeah. I know.”

“I need you to think for a second, just a second. Why would I forget one of the most painful experiences I’ve ever had?” Isa paused his swimming and let Lea circle back so he could still be talking to Isa while looking down from above. 

“I was kinda hoping you’d still be unwilling to say it like that, but you’re right. I was just thinking about how glad I am that I can touch you now.”

Isa reached up to prick his finger against one of Lea’s spines, it barely felt like anything after years of getting used to it.“It’s been ages, aren’t you used to being able to touch me without being incredibly careful by now?”

“Doesn’t mean it doesn’t make me happy.”

Isa laughed and looked up at Lea, reaching up and cupping his face to make sure they locked eyes. He couldn’t deny Lea being so outwardly sentimental was something he loved about him. “What was your point, Lea? Did you have one or did you just want to be a dork?”

Lea moved his hand over Isa’s and smiled. “I’m just thinking about it. I was really scared you weren’t going to be my friend anymore because of that and here we are, you’re in love with me and-”

“Don’t know who said that.”

“And I love you.”

“As you should.”

“You refused to let me know you were hurting that bad, you were really strong. You’re always so strong. I just love you.”

“Sappy. Is something going on?”

“No. I really was just thinking about how nice it is to not have that happen anymore. No poisoning my friend with hugs. Now I just bother my boyfriend by being clingy.”

“Sounds like you’ve had a couple changes, then. Why are we just talking about the almost killing me part of the story?”

“Because I’m trying to get to a point.”

“You said you didn’t have one.”

“Ugh! Just stop making fun of me for two seconds. You’re obnoxious.”

“Oh? Am I really the obnoxious one?”

“Yes! Why do I even like you?”

“I’m told you’re in love.”

“Wish I wasn’t in love with someone so mean to me.”

“I’m not mean to you. I could be. Do you want me to be mean to you?”

“No. Isa.”

“Then you know I’m being as nice as I can be?”

“Isa, can you just shut up and let me talk?”

“Hah, you think I’m able to keep you from talking? You?”

“Alright, shut up.”

“Really rude to keep saying that.” Moving up in the water to press his lips to Lea’s for a moment, Isa laughed. “You like hearing me talk. You enjoy my voice.”

“If you’d let me get to my point, Isa.” He left emphasis on the second syllable as he waited to be interrupted. When there was no interruption, he sighed. “I’ve been thinking about that because of how many things we still do come from not being able to touch you. When you kiss me outside of saying hey, it makes me remember watching Aeleus help you into the castle when I hugged you. Y’know, that should’ve had you paralyzed?”

“Yes, I’m aware. Are we really going over some backstory? Can’t we just continue this swim, head up to the beach, and relax there while it’s empty?”

“Am I not allowed to talk to my best friend anymore?”

“You are, but your boyfriend is getting impatient.”

“Then tell him to stop being an asshole.”

“He’s not about to listen, he’s just as stubborn as you are. Now, seriously, come on. There’s nothing we can’t talk about while relaxing somewhere even just a little safer than open ocean between islands.”

“Fine.”

“And I bet you don’t remember what your point was anyways.”

“I just told you what it was.”

“Oh? Was that it?”

“I hate you.”

Isa laughed and rolled his eyes, deciding to let that empty statement stand, returning to the other part of what he’d been saying. “We wouldn’t be between islands if you just remembered where we were going.”

“You could’ve told me I was swimming the wrong way.”

“You’re almost always ahead of me. It’s your fault for going so far so fast.”

“You could’ve noticed.”

“Excuse me for trusting the one who decided to take the lead.”

“You weren’t even trusting me, I know you better than that.”

“Fine, I was laughing at you for going the wrong way, but we didn’t run into any humans with nets, so it’s fine.”

“If that’s your metric, then, yeah, I guess. You sure you’re going to be fine doing your job when we get back?”

“If I’m too tired for the day, the world won’t fall apart if I don’t go in.”

“But you will.”

“Yes, I will. Of course I will. You will too.”

“Nah, I’m gonna skip out. Be irresponsible and sleep all day. Place won’t fall apart without me.”

Isa rolled his eyes and wrapped his hands around Lea’s wrists carefully, webbing between his fingers getting in the way of a full and comfortable grasp. He wasn’t going to say it aloud, but he really did want to just sit on the beach with Lea and look up at the moon until they were too dry to stay on land. “Lea, start moving, I want to get home eventually, but the moon is full tonight.” 

“You’re the one who stopped?”

Isa didn’t respond to Lea and instead opted to swimming forward with a small tug of Lea’s arms before letting go to continue swimming. He could be much faster when he wanted to be, a tuna tail was much better suited to going quickly than anyone who had only met Isa alone would be led to believe. Lea had to fight to keep up with Isa.

“Hey, Isa, slow down.”

“You can keep up, I believe in you.”

“Why am I dating you?”

“Why am I dating someone so slow?”

“Ugh! Fine. I don’t want to race, though, so slow down a little bit?”

Isa fell back, swimming at Lea’s pace and bumping their hips together. Lea still had the tendency to be careful around other people, despite Isa being all but completely immune to his sting because of the constant exposure. Isa had no such care. Lea responded to the bump by wrapping his tail around Isa’s, taking a position most used for comfortable relaxing while not moving.

“You really don’t want to let me see the moon above the water tonight, do you?”

“We’re still moving. You know how to pull me around, I know you do.”

“You’re lucky your tail isn’t as short as your dad’s is.”

“And you’re not. Pull me along.”

“Don’t be lazy.”

“Too late. I’m comfortable. And I know you can do this for a significantly longer time.”

Isa just sighed, shaking his head at Lea’s dorky actions. He loved Lea a great deal, but sometimes it was difficult… this was not one of those times, Isa found, as he glanced back to look at Lea’s smirk. 

They didn’t have that far to go, so the rest of their swim was in silence. They pulled themselves onto the deserted beach carefully and hacked the water up out of their lungs.

As soon as they were comfortably on the beach and breathing air, Lea flopped backwards into the sand and groaned. “I will never be used to that.”

“What?”

“Having to cough up that much water.”

“You’ll never get used to anything different than your first two years alive, will you?”

“Oh, shut up. You wanted to lay here and talk and look at the moon, so lay down with me.”

Isa rolled his eyes and laid down next to Lea, holding his arm out so he could be leaned against if Lea decided he wanted to. And of course Lea wanted to.

Just as Lea got comfortable, there was a sound of footsteps that was just too close for comfort. Lea moved away and began to slide back into the water and Isa followed behind him.

They got into the water just as a pair of human children locked eyes with them. 

“Wait, no, don’t go!” One of the children called out to the mermaids, reaching his hand out only to have the other grab him and hold him back.

“Sora, leave them alone. Kairi didn’t want to be seen either.”

“Yeah, but… We’re friendly.”

The mermaids stared at the gently arguing children in confusion, slowly backing up in the water so they could have a good distance between them. Where had they picked up this human language? 

Suddenly, Lea realized the humans had said a name.

“...Did you say Kairi?” Lea was too curious to continue the act of self preservation Isa was still anxious to do, but not without Lea. He knew that and he could see Isa ready to bolt, but he needed to know.


	2. Chapter 2

Isa had his tail wrapped around Lea, prepared to pull him away if his talking to the humans lasted much longer. It was one thing to be seen, humans could be taken care of if they were too curious or invasive, it was another to stay there and have a discussion of any sort with them. Lea knew that. Lea also knew that Isa might have a high resistance to his venom built up, but if he waited too long, it would start to hurt him.

So he hoped the human would respond quickly.

And the human with white hair did, after a sigh and a nod towards the other one. “Yes, we know someone named Kairi. Mermaid girl.”

“Mermaid. That’s a weird word for us,” Lea said, getting an angry look from Isa who had begun to tug at Lea.

The brown haired human looked confused for a brief moment, tilting his head and squinting his eyes. “Do you know Kairi?”

“Yeah. She’s my cousin,” Lea said with a small nod before Isa’s hands came up and grabbed him by the shoulders.

“We’re leaving. And telling her parents what she’s been up to. It’s not safe.”

“Aw, c’mon, Isa, they seem nice enough. Kairi’s not stupid. We were sneaking up here too and got caught by the same humans, it wouldn’t be fair.”

“It is because we’re not sticking around, Lea. She did.” Isa’s words were quiet and getting harsh. “Don’t be stupid.”

The brown-haired human looked confused. “Are you going to make Kairi stop visiting? I had a present for her. Riku and I made her a present I think will be fine in the water this time.”

Lea squirmed out of Isa’s grip and turned to look at him, arms crossed over his chest as he waited for him to give up and let them stay with the obviously harmless human kids. He was distracted by a familiar head popping up out of the ocean and it was apparently too obvious on his face because Isa squinted his eyes and turned to look back.

Isa sighed. “Fine. I won’t say anything.”

Lea grinned and nodded at Kairi, watching her go from a slow and careful approach to a full-speed approach and a hug for Lea. 

“Hey, Kairi. You gonna explain to Isa why you’re hanging out with humans before he decides it’s too dangerous for you?” Lea said, gently ruffling the girl’s hair with a grin on his face. He always liked to see her, she was a good kid.

“Sora and Riku are very nice, Isa. They’re my friends and they haven’t told anyone else about me.” Kairi moved away from Lea and swam up to the beach, resting her head on her hands as she looked up at the two boys. “Hi, guys.”

The brown-haired boy immediately sat down and reached out his hands towards Kairi, grinning when the girl very carefully placed her hands on his. “You’re late!”

“I am not. I don’t have a time that I’m supposed to be here. Sorry if I made you wait, though.” 

Lea elbowed Isa as the human interacted with Kairi and the moment Isa’s head moved in defeat, sigh escaping his lips, Lea swam back to be closer to the humans again. 

“Sorry for the freak out, but if Kairi trusts you, I’m gonna trust her judgement. She knows when people aren’t being right.” Lea grinned, pausing for only a moment and nearly letting the humans have time to speak. “I’m Lea, that’s Isa. Nice to meet you two.”

“Uh. I’m Sora! That’s Riku. We’ve been hanging out with Kairi… Uh. Would more time or less time get her in less trouble?”

Lea grinned and shrugged, looking at Isa then again to the human children. “I’m not gonna let her get into trouble for something Isa and I sneak off to do just ‘cause a couple of harmless humans saw her and she did the fun thing and befriended you kids.”

The human that was named ‘Riku’ finally spoke again after sitting down next to the one named ‘Sora.’ “It looks like we should be careful around you, right?”

Lea blinked then nodded with a short laugh. “Yeah. You shouldn’t be jumping in here to join me or anything if you wanna keep being alive.”

“I’ll remember that. Thanks.” Riku seemed to be the more cautious of the two.

“Of course we can’t touch him, he looks like a weird lionfish. Those can kill people, Riku!”

“Asking to make sure when we’ve seen two people wrapped around him makes sense, Sora.”

Sora seemed to think about that for a second, looking at Isa then at Kairi. “How do you guys do that?”

“It’s a build-up of immunization. Resistance, really. It hurts no more than a small jellyfish’s sting at this point. Kairi should be approximately the same way, seeing as she’s related to Lea.” Isa was willing to explain things when asked, even if he didn’t completely trust who Lea decided to talk to. Lea always appreciated that.

“Oh, right! She’s your cousin, that’s cool. Why isn’t she a lionfish?” Sora asked, looking between all three mermaids.

Riku shook his head. “Sora, obviously the parents they have that are siblings aren’t the lionfish. Like… If his dad and her mom are siblings or something, they’re… I don’t remember what you are, Kairi.”

“It’s actually his mom and my mom.” 

Kairi spoke to the humans with a such a big smile on her face that Isa put his hand on Lea’s shoulder. When Lea looked back to Isa, he saw a soft expression. They could both recognize love in other people and Kairi obviously adored these humans. The girl was easier to read than most, her gentle bioluminescence grew stronger with joy.

Lea nodded at Isa and reached over to ruffle Kairi’s hair. “Hey, we’ll leave you kids alone. Anyone else on this island right now?”

“No, we only come to meet with Kairi when we know everyone else has already gone home. Our parents just think it’s some light teenage rebellion, but they trust us.” Riku said, still standing back slightly in a position that mirrored what Isa’s had been before recognizing the trust Kairi had placed in these humans. Lea couldn’t help the laugh that escaped his lips despite his best efforts.

“What’s so funny?” Sora seemed to be the curious one, the one willing to ask whatever came to his mind. It was disarming, it made Kairi’s trust make all the more sense.

“… Riku, right?” Lea looked at the boy with silver hair. Riku nodded in response. “You almost remind me of Isa.”

“Ew, Lea, no,” Kairi said almost immediately, causing Lea to laugh even harder than before.

“Oh, is it like that?” Isa raised an eyebrow at the girl, an expressionless face being betrayed by amusement in his eyes. 

“Is what like what? Kairi, what’re they saying?” Sora resumed his questions, curious about what was happening in front of him with the new mermaids and his friend.

“Lea was going to leave… with Isa.”

“Yeah, we’re going to go find somewhere to leave you three alone,” Lea said with another laugh, moving back to ensure his tail was far enough away from the humans so none of the spines would accidentally hit a child then swam of quickly, breathing in the water as he dove under the water.

Isa spent a moment watching Lea swim away before turning to face the children. “We do plan on checking on you occasionally now. Kairi trusts you, but I don’t trust adults you two likely know who may look for you if you’re breaking rules. Be careful. Kairi, take care of yourself.”

Kairi nodded and waved as Isa turned to follow Lea.

Sora continued to look around, confused. “I still don’t get it. What was wrong with Riku reminding him of the tuna man?”

**Notes for the Chapter:**

> I'm going to continue on with this! Maybe I'll actually write out childhood stuff for Lea and Isa eventually. I'll probably be shifting focus to Kairi, Riku and Sora next chapter? I'm not entirely sure, though.


End file.
